I don't think there are data limits on Wifi. Do you know what network it's trying to connect to? It doesn't require further authentication does it? Could be it's trying to connect to something other than you think is which is Open but requires further authentication.

I had a problem with wifi connection my old nexus 7. I found something on the net which said to turn off the wifi on your device, go into advance wifi settings and set to 5ghz, switch wifi back on, then go back repeat the steps but set the wifi back to auto.

I think I may have even hit the "forget this network" and then reconnected to it after doing the above. It worked and had no problems with it after that.